I've never been a huge fan of Wes Anderson's films: the more formalistic and stylized they got, the less they interested me. But I do enjoy stop-motion animation, and it seems to be a fine fit for Anderson's obsessively detailed visual sense, where he can finally have his characters do exactly as he pleases - because they are literally puppets. In a sense, Anderson is applying a lo-fi approach to a trend that other control freak directors like Robert Zemeckis, Peter Jackson, and James Cameron are indulging in: supplanting unpredictable human actors with easily manipulated CG models.
Regardless, since we allow these animated figures a bit more silliness than we would endure from flesh-and-blood performers, the slapstick antics in Fantastic Mr. Fox - and there are many - are infinitely more charming than the lame exploits in Anderson's The Life Aquatic, the film that really turned me off of his work. (I didn't even bother seeing The Darjeeling Limited.)
This movie retains Anderson's dry wit (with substantial help from his frequent cowriter Noah Baumbach) and quirkiness, but is far more lively and cohesive than his last few films. Part of this could be that he is working off a classic children's story by Roald Dahl. (Reportedly, Anderson went to the late Dahl's home and stayed there for a while for inspiration for the production design.) Or maybe the animators just enjoyed moving the little characters more quickly than usual.
All in all, this simple story about the titular fox (well-voiced by George Clooney) who starts a war with three nasty human farmers after a few clever heists is clever, funny, and altogether satisfying. (Of special note is Alexandre Desplat's whimsical score.) It really is, as one critic has said, a toy box of a movie. Children should enjoy it very much, even as their hipster parents nod agreeably at the wry dialogue. I had a good time myself.